The configuration property type, The configuration property modifiers – Echelon LonTal Stack User Manual

Page 184

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Appendix C: Appendix C


Neuron C Syntax for the

Model File

cp_family

Declares the configuration property as part of a configuration file.
The cp_family declaration is repeatable. The declaration can be repeated

two or more times, and, as long as the duplicated declarations match in every

regard, the compiler treats these as a single declaration.
The alternative to declaring a configuration property as part of a

configuration file is to declare a configuration network variable, as described

in Declaring a Configuration Network Variable.

The Configuration Property Type

The type for a CP family cannot be a built-in Neuron C type such as int or char.
Instead, the declaration must use a standard configuration property type (SCPT)

or a user configuration property type (UCPT) defined in a resource file. There

are several hundred SCPT definitions available, and you can create your own
types using UCPTs. The SCPT definitions are stored in the standard.typ file,

which is part of the standard resource file. There can be many similar resource
files containing UCPT definitions, and these are managed by the NodeBuilder

Resource Editor.
In contrast to an ANSI C typedef, a configuration property type also defines a
standardized semantic meaning for the type. The configuration property

definition in a resource file contains information about the default value,
minimum and maximum valid values, a designated (optional) invalid value, and

language string references that permit localized descriptive information,

additional comments, and units strings to be associated with the configuration
property type.

The Configuration Property Modifiers

The configuration property modifiers are an optional part of the CP family and

configuration network variable declarations.

The syntax for the cp-modifiers specification is:
cp-modifiers :

[ cp_info ( cp-option-list ) ] [ range-mod ]

cp-option-list :

cp-option-list , cp-option

cp-option

cp-option :

device_specific | manufacturing_only |

object_disabled

| offline | reset_required

range-mod :

range_mod_string ( concatenated-string-constant )

The cp-option keywords can occur in any order. There must be at least one

keyword. For multiple keywords, a keyword must not appear more than once,
and keywords must be separated by commas.
The cp-modifiers begin with the cp_info keyword followed by a parenthesized list
of one or more of the following option keywords:
device_specific

Specifies a configuration property that is always read from the device instead

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